Fusible locking member for sprinkler heads



Oct. 31, 51933. R. H. RUSSELL 1,932,805

FUSIBLE LOCKING MEMBER FOR SPRINKLER HEADS Filed Dec. 2. 1930 flier-z IJTaJJ'eCC 2 I S y mu m. 6. I M 7 l EPatented Get. 31, 1933 sirso STA-res .5 FUSIBLE LOCKINGCMEIVIBEREOR SPRINKLER HEA-DS Robert H. Russell, Worcester, Mass, assignor'to Rockwood Sprinkler Company oiliiassachusetts, Worcester, Mass., a oorpdxation'of Massachusetts Application December 2, 193i). Serial N0. 499,520

2 Claims.

This invention relates to a fusible locking mem ber. particularly designed for use inrasprinkler heads It is the-object of 'my invention to-provide a locking member for such purposes so designed that it will respond very quickly to a change in temperature.

A furtherobject is to provide a locking member which will. be reliable and certain in operation and which will beconvenient and economical to manufacture.

An important feature of the'invention relates to the use of relativelythin sheet metal in certain parts and to the-provision or a side'flange con struction by which theassembly of the parts'is facilitatedand the operation of the locking mel ber is made more certain and i'norese'nsitive.

a preferred form of the invention is shown in the drawing, in which l is a side elevation of a sprinkler head having my improvements embodied therein;

Fig. 2 is a plan view of my improved locking member, looking in the direction of the arrow 2 in l;

5; Fig. 3 is a side elevation of one of the thrust elements of the locking member;

e is a plan View thereof; Fi 5 is a plan View of a blank from which the thrust element or" the locking member may be conveniently formed;

Fig. 6 is a side View thereof;

Fig. 7 shows the blank partially formed;

Fig. 8 is a sectional View, taken along the line 8-8 in Fig. 7;

9 is a sectional view of the complete looking member, taken along the line 99 in Fig. 2; and p Figs. 3-0 and 11 are detail sectional views, taken along the line 1o 1c in Fig. 7 but showing slight modifications.

While adapted to general purposes where a fusible locking may be used, my improved locking member is particularly designed for use in sprinkler heads, a common form of which is shown in Fig. 1.

A threaded member or nipple 10 is provided with a cap 12 closing the passage therethrough and held in place by a post 14 engaging one end of a lever 15. A locking member 16 is positioned scrbetween shoulders at the lower end of the post i l and at the outer end of the lever 15 respectively. A compression screw 17 engages the up? per side. of the lever 15 at a point out of alignment with the post 14 and acts through the memhere 14, 15 and 16 to apply pressure to the cap 12 and prevent the escape of waterfrom thenip ple 10. r a

With the exception of the locking member '16; the parts thus far described are of'a usual comm'ercial'construction.

My present invention relates specifically to the construction of the locking member lfir' This locking memberlfi comprises two thrust ele meme-20 and-21'. The thrust-element zo'is proe Vided with a shoulder 22 (l 'ig. -3) adapted to :1 engage an end surface 2% (Fig. 7) of'th'e thrust member 21. The extreme end portion =25 of the thrust element ZOengages a shoulder at the outer end or" the lever'l5, as indicated Fig.1 and as previously described. 70,:

The opposite end portion 26 of the thru'st'element 20 is formedasan elongatedtongue, which pi eierably beoomesgradually thinner toward its extreme outer end, indicated at 27. The assembled position of the thrust element 20 is clearly shown in Fig. 9.

The thrust element 21 is preferably formed from a blank of thin sheet metal having substantially the outline indicated in Fig. 5. This blank is preferably made of an alloy having non-corrosive properties but may be formed of any metal having suificient strength and suificient resistance to corrosion.

The blank is first subjected to a press operation by which the sides 30 and one end portion 31 are bent at an angle to the body portion, as clearly indicated in Figs. 7 and 8. The end portion 31 is then further bent over and downward, as indicated in Fig. 9, but the extreme end portion 32 is inclined upwardly away from the body V or" the thrust element 21 and so shaped as to form a sort of hook to hold a lump of fusible solder S which extends over the end 27 of the thrust element 20.

When the parts are assembled, it will be evident that the end 2'7 of the thrust element 20 does not quite engage the upwardly bent hook portion 32 of the end portion 31 of the thrust element 21. Consequently the thrust element 2 0 is free to swing about its shoulder 22 after the device has been subjected to heat sufficient to melt the solder S which is used to hold the parts together.

It will be noted that the portion of the solder S between the parts 27 and 32 is substantially in shear and thus holds the parts much more reliably than in a construction Where the parts are merely sweated together.

In assembling the locking member, the parts 20 and 21 are placed in the relative position shown in Figs. 2 and 9 and a suitable solder with a desired melting point is then flowed between the parts and also around the edges and between the adjacent portions 27 and 32. The application of this solder is much facilitated by the presence of the flanges 30 which confine the solder laterally.

The thrust element 20 may be provided with ribs or corrugations and the thrust element 21 with corrugations 41 for increased stiffness, thus permitting thinner or weaker metal to be used. The provision of these ribs and corrugations not only increases the stiffness of the parts but also results in a better bond between the adjacent surfaces. The ribs and corrugations tend to prevent the formation of the air or gas pockets which otherwise often form between unbroken flat surfaces when being sweated together.

When the locking member is in use, the flanges 30 act to direct the rising currents of warm air against the soldered surfaces between the flanges and thus tend to increase the rapidity of action of the device.

The use of thin sheet metal for the thrust element 21 and the use of relatively thin metal for the tongue portion of the thrust element 20 also tends to increase the speed of action of the device and to cause the sprinkler head to be released more promptly upon an undue rise in the surrounding temperature.

If a greater shearing effect is desired, ears or lugs 42 (Figs. 2 and 7) may be pressed upward at each side of the member 20, and near the end 27 thereof, thus producing a shear effect at each side of the member 20, as well as at the end thereof.

In Figs. 10 and 11 I have shown slight modifications in which side lugs (Fig. 10) or 51 (Fig. 11) are formed by punching and bending inward parts of the side flanges 30 leaving the fiat or body portion of the element 21 intact and continuous.

Having thus described my invention. and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim,is:

1. A fusible locking member for a sprinkler head comprising two thrust elements positioned face to face and having portions abutting endwise, said thrust elements being secured in assembled relation by a readily fusible solder, said first thrust element having outwardly inclined flanges spaced from the sides of said second thrust element, and portions of said side flanges being displaced inwardly adjacent the side edges of said second thrust element and holding portions of solder in shear.

2. A fusible locking member for a sprinkler head comprising two thrust elements positioned face to face and having portions abutting endwise, one of said thrust elements being formed of relatively thin metal having side portions projecting upward to form flanges at each side of the second thrust element, said two thrust elements being secured in assembled relation by a readily fusible solder which also overlies one end of said second thrust member, and said side flanges being more widely separated and of greater height adjacent the overlying solder at one end of said second thrust element, and said first thrust element having displaced abutments projecting into the enlarged space enclosed by said flanges at the sides of said second thrust element, said abutments holding portions of said solder in shear.

ROBERT H. RUSSELL. 

